I'm certainly interested in some of these changes, but have to echo thoughts already posted here.
4hr Re-calcs: I think every 4hrs will be too excessive. Doing every 6hrs, 8hrs, or 12hrs seems to make more sense. Both so guilds can still use some bits of strategy, but also because of the addictive nature of games. Do not discount the fact that people can and do fall victim to addiction without realizing it, and having too many re-calc times could impact a portion of players in that they completely forego real life for the game, until someone in their life intervenes and then you 100% lose that player (and while this is not Inno's fault, if you can avoid/mitigate it, why wouldn't you?). I know this sounds extreme, but I still remember the days of WoW cults. They may still exist, but hopefully not like they used to. Very scary stuff. Having multiple re-calcs is a good idea because of time zones, but you need balance here. Too many and you totally destroy what GvG is good for: strategy and team-building. Too few and you don't resolve the actual issues. So I think no more than 3 or 4 a day is appropriate. 6 is absolutely overkill.
Also on this note, sure you won't be able to move HQ more than once a day, but it won't matter with re-calc being so often. The HQ move becomes irrelevant. So, while I think it's admirable that you want multiple re-calc times, I do think something else has to be put in place to keep the HQ move relevant. Perhaps instead of the sectors losing protection at each re-calc, they have a time-down? So after the first re-calc they can be hit, but the defense is high. In addition, since they're in time-down, you cannot attack from them. IE: If the sector now, after re-calc, would have a 75% bonus to the defending armies, then with the new multi-re-calcs we instead would see that on the first re-calc of the day the sector gets a 175% bonus (so comparable to GE, essentially). At the second one, that drops to a 125% bonus. At the third, 100% bonus, so on and so forth until 24hrs are up, the shield comes down completely, and you're at the standard 75% bonus and thus out of the time-down. The graphic doesn't even have to be that involved, you could just have the little protection shield slowly draining until it's empty and gone (which will also indicate when the 24hrs are up) This way the map stays fluid (as I assume is part of the goal), but allows for some strategy to still be at work AND the HQ move is still important. Heck, it'd even open up for some interesting strategy at timing
when to take sectors.
I would have it remain that the HQ move can only be done once every 24hrs, and that dropped sectors cannot be retaken for 24hrs.
Personally, I'm excited at the prospect that this gives to making GvG more competitive, which in turn could add to the excitement. It just needs to be done well.
Point Farming: It definitely makes it more interesting if by dropping a sector the troops are randomized. This will change it so that if you want to do a retake to protect something a little longer, then you can't just fill with rogues and go for it. However, I absolutely agree that on AA it needs to default to the LOWEST era possible, and not the highest. Defaulting to the highest era will only exclude everyone not in that era essentially, but as others have pointed out, allow players to farm points by just filling in with garbage low era troops and dropping it so it becomes high era troops.
AA and Spears: I cannot deny that there was a lot of potential to use AA as a training ground to teach new folks GvG because of this, on the cheap. However, this is one change I can live with. Bronze Age players cannot even play in GvG (you don't unlock it until Iron Age), and so with that in mind I can understand restricting troop age to a minimum of Iron Age. This will actually force some new strategy.
Checkboxes: I like that you won't have to see certain things again, to make sieging faster. On that same logic, can we please remove the menu to enter a sector when it is under siege, and make it so any sector you're sieging acts like an NPC sector under siege? By this I mean that you just automatically pop open the battle screen to select troops, instead of having to open a menu, and select the battle function. When I'm trying to take a sector I honestly do not care about the guild profile of the one who owns it or similar. Similarly, if a sector I own is under siege, please just let me click on the sector and have it open to my troop selection. You can't move HQ or release a sector that's under attack anyways, no need for the menu options.
That's all that comes to mind right off. I look forward to seeing what bugs are going to be fixed, since that is mentioned. If I think of anything else, I'll gladly share it. I love GvG, so I'm happy to see some attention being paid to it. I just hope that this truly improves GvG.